Chronic hepatitis B virus (HBV) infection remains a global public health burden around the world. Investigating the disease process of chronic hepatitis B (CHB) is essential to individual management in clinical practice. According to American Association for the Study of Liver Diseases (AASLD) 2018 Hepatitis B Guidance, CHB can be classified into four phases: immune-tolerant CHB, HBeAg-positive immune active CHB, inactive CHB and hepatitis B e antigen (HBeAg)-negative immune active CHB. Antiviral therapy is recommended in patients with HBeAg-positive or -negative immune active CHB patients to reduce the incidence of liver cirrhosis and hepatocellular carcinoma, while periodic monitoring is recommended for inactive carrier and immune-tolerant CHB patients. However, a substantial proportion of patients fall into an indeterminate phase whose serum HBV DNA and alanine aminotransferase levels do not fit well into these well-described phases. Most of CHB patients with indeterminate phase are HBeAg negative. However, the clinical outcomes of these patients remain unclear. Therefore, the purpose of this study is to investigate the clinical outcomes of HBeAg-negative chronic hepatitis B patients with indeterminate phase.

Inclusion Criteria:

1. Hepatitis B surface antigen (HBsAg) positive over 6 months
2. Age ≥18 years
3. Treatment-naïve
4. HBeAg negative, anti-HBe positive
5. HBV DNA >2000 IU/mL
6. Persistently normal alanine transaminase (ALT)
7. Liver inflammation <G2 or A2 and liver fibrosis <S2 or F2 before enrollment, or liver stiffness >8 kilopascals (kPa)
8. No family history of liver cirrhosis or hepatocellular carcinoma

Exclusion Criteria:

1. Coinfection with hepatitis A virus, hepatitis C virus, hepatitis D virus, hepatitis E virus or human immunodeficiency virus;
2. Coexisting of hepatocellular carcinoma and other malignancy, or alpha-fetoprotein >upper limit of normal at enrollment;
3. Presence of liver cirrhosis;
4. Alcohol abuse within the last year (ethanol: male >40 g/d, female >20 g/d; or heavy drinking within 2 weeks before enrollment: ethanol >80 g/d), or history of drug abuse;
5. Participating in other clinical trials in the last 3 months;
6. Coexisting of autoimmune liver diseases;
7. Pregnant or planned pregnancy in a short term or lactation patients;
8. History of severe heart disease, mental disease;
9. Uncontrolled diabetes, hypertension, thyroid dysfunction, retinopathy, autoimmune diseases;
10. Neutrophil count <2×10^9/L and/or platelet count <100×10^9/L;
11. History of organ transplantation or preparing for organ transplantation;
12. Using immunosuppressive drugs;
13. Undergone organ transplantation or preparing for organ transplantation;
14. Receiving immunosuppressive agents;
15. Patients thought by the investigators not suitable to participate in this study.

HBeAg-negative chronic hepatitis B patients with indeterminate phase